Such a method is disclosed in Applicant's international patent application PCT/SE2010/051172, filed 28 Oct. 2010, (priority date 30 Oct. 2009). A similar method is also previously known from the German published specification (Offenlegungsschrift) DE 4406150 A1 (Pumpe et al). In this prior art system for hot water distribution in a building, there is a pressure sensor 10 in a liquid chamber adjacent to the warm water tap. When tapping water, an electric signal is fed back through an electric line 11 to a centrally located control device 19. Accordingly, there is a need for separate electric cables being drawn from each hot water tap to the central control device.
Another major drawback with this known method is that, in order to avoid a high pressure peak and strong noise when the liquid (the hot water) reaches the liquid tap during a refilling operation, an air injector (17) has to be used so as to make the hot water liquid “elastic”.